A conventional piano includes a keyboard for operating the hammers, which strike the strings. Additionally, pedals are provided near the ground, for providing additional control. Commonly, a piano will have two pedals, namely a left-hand (una corda) pedal and a right-hand, damper pedal, which controls the length of time the sound is sustained. Additionally, some pianos include a third (sostenuto), damping or sustaining pedal, for controlling just part of the strings. The right-hand pedal is the most frequently used. Pianos come in a wide variety of shapes and sizes. Two principal types of piano are the upright piano and the grand piano. In the upright piano, the pedals extend directly from the main body of the piano, whereas for a grand piano the pedals extend from a separate pedal box.
As the basic height relationship between the pedals and the keyboard is determined by the design of the piano, learning to play a piano with pedal action presents difficulties for a yound child. If the child is at the right height to comfortably reach the keyboard, then the pedals will be too far away. A simple solution is simply for the child to only use the keyboard, until he or she is big enough to reach the pedals. However, this is undesirable. It is preferable for a child learning to play the piano, to learn to use the pedals as early as possible, and this can heighten musical expression and the childs's enjoyment.
It is also to be noted that, even if the child is not using the pedals, it is desirable for the child's feet to be comfortably placed on a level stool or the like.
This problem has been recognized, and many proposals have been made for dealing with it. The following patents all disclose mechanisms intended to deal with this problem, all of these patents being U.S. patents with the exception of the first patent which is a Dutch patent:
36,882 (Netherlands) PA1 U.S. Pat. No. 198,893 Mathias PA1 U.S. Pat. No. 688,416 Hopphan PA1 U.S. Pat. No. 759,959 Bates PA1 U.S. Pat. No. 1,007,980 Schreiner PA1 U.S. Pat. No. 1,040,397 Paczynski PA1 U.S. Pat. No. 1,269,717 Kirk PA1 U.S. Pat. No. 2,030,929 Miyashita PA1 U.S. Pat. No. 2,213,800 Ege PA1 U.S. Pat. No. 2,245,314 Willis PA1 U.S. Pat. No. 4,418,604 Kim
A wide variety of different mechanisms are disclosed in these patents. They all suffer from various disadvantages. Many of them are complex and would be costly to make. Other mechanisms are only suited for a particular type of piano, and could not be applied to both grand pianos, and upright pianos.
Many of them disclose height adjusting mechanisms, which rely upon the simple principal of a shaft engaging a tube or cylinder. The two elements are held in relation to each other by a ratchet mechanism or screw mechanism. However, this severely limits the height range of the stool. The minimum height must be at least the height of the shortest element, whilst the maximum height must be less than twice the height of the longest element of the pair. In many cases, it is desirable for a foot stool to be adjustable through a wide range, e.g. through a range where the maximum is three times the minimum height.
A further disadvantage of some of these earlier proposals is that they employ relatively complex mechanisms for transferring the movement of an auxiliary pedal to the main, piano pedal. Many of them have a vertical action, which it has been found does not always function well. It is desirable that the mechanism should be robust, and transfer the movement of the auxiliary pedal to the main piano pedal in a reliable manner. Ideally, the displacement of the auxiliary pedal should be comparable to that of the main, piano pedal.
Another disadvantage of many known designs is that the stool is placed right up against the piano. It is to be realized that, for a yound child, a stool with pedals needs to be both higher and the pedals nearer than the main piano pedals. This ensures the child is in an optimal seating position at the piano.
A further disadvantage of earlier proposals is that they employ relatively simple and crude mechanisms for transferring the displacement from the mechanism of the device to the main, piano pedals. Preferably, this transfer of the displacement or motion should be accomplished in a smooth, reliable manner. It is desirable that the user should obtain the full feel of the main, piano pedals at the auxiliary pedals.